Alternating-current apparatus.



No. 869,244. I PATENTED OCT. 29. 1907.

s. HUBBARD.

ALTERNATING CURRENT APPARATUS.

APPLICATION rum) JULY 2, 190a.

ALBERT S. HUBBARD, OF BELLEVILLE, NEW

JERSEY, ASSIGNOR TO GOULD STORAGE BATTERY COMPANY, A CORPORATION OF NEW YORK.

ALTERNATING-CUBRENT APPARATUS.

Specification of Letters Patent.

Patented Oct. 29, 1907.

Application mainl a. 1906. Serial No. 324.303.

To all whom it may concan: I

Be it known that I, ALBERT S. HUBBARD, a citizen of the United States, and a resident of Belleville, Essex county', State of New Jersey, have invented certain new and useful Improvements in Alternating-i Current Apparatus, of which the following is a specifivv :ation.

My invention relates to electrical systems of distribution of the' alternating current type and comprises means especially adapted for the automatic regulation of such systems. I have devised the various features of my invention with specificreference to theregulm tion of a storage battery used in connection withjan alternating current system to steady the load' on the alternating current generator, but the specificmeans that I have devised to carry out my method are appli cable to other types of systems.

As is well known, in all alternating current systems having in whole or in part inductive or capacity load 7 there occur changes of power factor in the system, that is, the phase relation of the voltage and the current changes. With such change of power factor the true energy or load upon the system bears a different relation to the product of the voltage and current because a certain amount of apparent energy is what has been termed wattless current.

My invention involves the production of a current that varies with the current or voltage changes of the circuit but which is so modified by changes of power factor as to 'corrospondto the true energy of the system rather than to the apparent energy thereof. It involves further the employment of such a current for purposes of regulation, including the regulation of the field of a dynamo, in accordance with a varying current of this character. It also involves the regulation of a regulating battery for an alternating current system by a varying current of this character, or, broadly. the varying of the battery current in accord with the changes of a component of the true energy as distin: guished from a component of the apparent energy. Preferably, this current I produce is varied in accordance with current changes of the alternating current system as modified by the power faction changes, My

invention more specifically involves the production of.

such a current as I have specified by by-passing from the circuit to which such current is to be supplied a current that varies when the power factorchanges, the current in the bypass or local circuit beingpreferably zero as long as the power factor is unity so that when ever there is a leading or lagging curr nt the) is a current in the by-pass circuit.

The specific-apparatus constiumng manner feature of my invention comprises a rectifier of the induction type, having sets of commutatorbrushes electricallydisplacod from each other, one of said sets being preferably piaced at the points having a zero difference of potential when the power factoris unity, whereas the other set of brushes is preferably placed at points where the difference of potential is maximum when the power factor is unity. The two sets of brushes are connected to difierent circuits. I have shown this rectifier supplied with current -from the alternating current circuit, whichcurrent is provided. by transformers in series the alternating current generator, and the rectifier current is employed for regulating the battery current,

a direct current regulating coil for the-batterybeing connected to the brushes having normally maximum potential, while a local circuit containing a resistance is connected to the brushes having normally zero poten- -tia'l. In this way as long as the power factor remains unity the current from the series transformers and the I current given out to the direct current regulating coil are in exact proportion, but when the power factor departs from unity the field of the rectifier is shifted relatively to the brushes causing the brushes, no longer to be respectively at the points of maximum and zero potential. If the extra set of brushes and the local circuit were not provided the voltage ac'rossthe series transformers would rise until the voltage across tho commutator brushes and the rectifier would rise sufficiently to produce a current in the regulating circuit corresponding to the change of current in the selies transformers. In other words, even though the brushes connected to the regulating circuitare no longer at the points of maximum potential, the transformation from the alternating current to the direct current side would still remain a true current transformation. As, however, the field of the rectifier shifts, the brushes normally at zero potential become subjected to a potential difference which will cause a current to flow in the local or by pass circuit, thus diverting current from the regulating circuit and making it unnecessary, if the parts are properly adjusted, for the voltage across the series transformers to rise. The result is therefore that the current in the rcgulating circuit is a resultant of the current in the alternating current circuit and the power factor of that circuit.

Although I have thusdescribed this rectifier device and the circuits and apparatus to which it is thus connected somewhat specifically, it will be understood that my apparatus and invention is not, in its broadest phase, limited'to all the various features I have described, as I believe it to be broadly new to employ the pair of brushes connected at points of normally zcro difference of potential and that thisfeature may be 7 used for various purposes. More specifically, how-- diagram which illustrates a system constituting a specific embodiment of my invention. In this diagram A indicates an alternating" current generator oi any type it being understood thattherv may be any nulnher of generators and that the generator or generators may-be rotary converters located at sub-stations if desiredQ B indicates any suitable form of rectifying device, as, for example, a rotary converter, the current to which is supplied by the generator A, while the direct current'supply is connected to a battery C preferside of the rotary converter and an alternating current I workcircuit on the other side thereof. 1

As so far described the system isinerely one in which a regulating storage battery and booster are employed to steady the load on a main alternating currentgenerator. In such systems it is most usual to so regulate the system that with a given'current load on the maingen erators the booster voltag'e'will' be zero arid the battery will float across the direct current side of the system neither charging nor discharging, Upon increase of current on the main generator a booster voltage is veloped in one direction causing or assisting the batteryto discharge and limiting the change of generator current. Upon a decrease of generator current below the. predetermined average a booster voltage is developed in the opposite direction causing the battery to charge and thus limiting the reduction of the current on the main generator.

The booster voltage is controlled by a suitable regulating apparatus/from coils in the alternating current circuit.

or counter machine E and the regulation of the booster voltage is effected by varying the field strength of this counter machine. This counter machine is, illustrated as having two windings, a substantially constant cur-' rent winding E connected across the direct current side of'the system and a regulating winding'E which is governed by changes in the alternating current'circuit. 'In order that the changes in the alternating current circuit may act upon the coils E I have provided transformers F whose primaries are in series with the generator A and whose secondariesare connected to the distributed windings on a rectifier of the-induction type which is diagrammatically indicated at 'G. This rectifier is prefera'bly devoid of motor action and is so illustrated. Some outside means must. therefore be ,provided to drive the rectifier synchronously. In the present instance this is accomplished by the synchronous motor H driven from the alternating current circuit. This motor drives the rectifier so that it rotates synchronously with the voltage oi the generator A. The regulating field coil E is connected to brushes 9 bearing on the commutator G of the rectifier. These brushes are preferably placed in the usual position for such brushes, namely, at the points-of normal maxi mum -voltage. This rectifier placed inthe regulating circuit and employed to provide current to theregulating coil of the direct current side of the system is more fully described together with its incumbent advantages in an application of Edward Van Wngenen In-the present instance the boosterfielcl win'ding 1) is connected. in series with a'regulating dynamo l filedfon date -herewith. When used-with poly phase currents as illustrated'in the'diagrain, a rotating field is produced and the rectifier is driven in a'directhe brushes g are. always maintained at the points of the alternating current circuit is unity.. I

'Assuming that the power factor of the alternating current circuit'is atunity and does not change then the operation of the apparatus as. sofar described is as fol a corresponding change takeslplace in the transformcrs F, anexactly proportionate change takes place in the circuit of the regulating coil and the counter ma: chine voltage and-therefore thebatteryvoltage; are" of the current in the main generator. Because. the. rectifier is devoid of motorl-actionno inaccuracy isj introduced due to-an'y tendenc'y of the rectifier topropel the synchronous motor, which tendency .wou-ld divert tion of the booster in accordance with changes of cur-. rent on the generator-A has frequently been referred to as a regulation" by changes of load onthe generator" A. Such regulation, however, applied-to inost corr'rmercial plants would in no way be either a true load regulation or even such a current r'e'gulationaswould bear any reasonable relation toiload changes. This is due to the character of changes of power factor that occur in such systems. Heretofore it has been assumed I that the flowing that a regulation in accordance with current changes would also properly compensate for changesof power factor and the wattless currents. caused by such 'ch'apge's; I have found that this is very far'from being a not necessarily bea'rany definite relation to the'amount of current supplied by the generator'and in any case'no satisfactory load regulation for an alternating current generator can be obtained if the attempt is made to regulate directly in accordance with changes of current. In accordance with my iinprovedmethod I regulate by a current that has a value correspondingto a'resulta'nt of the value of the current'on the main generator-and that of the wattless energy or power factor. To accomplish' this in the specific embodiment illustrated l have shunted or by-passed current from the regulating circuit .whenever the power 'factor departs from unity, varying the amount of such .by-passed currents in accordance with changes. of power factor. The-special apparatus whichl have devised and which forms part of my invention comprises specifically a pair of brushes g which are displaced about ninety electrical degrees from the brushes g sothat they bear upon the commutator G at points having a zero difference of potential when the power factor of the circuit is unity. Connected to these brushes 9 is-a local circuit G in which is placed an adjustable resistance I by which the apparatus may be adjusted forthe most advantageous regu-t lation.

When there is unity power factor on the circuit the current in the circuit G will be zero. I When however, the power factor departsfrom unity setting up wattless currents, the brushes 9 and 9 become displaced with reference to the polar line of the rectifier G sincethat tion opposite to that of the rotation of said field so that I x 7 0 .maximum potential assuming. that the power factor of low'sfUpon any change of'c'urrent on the generator'A- current from thecircuit of, the coil E Such regulaproperly governed in direct accordance with changes power factor would hear such relation to the current 100' proper assumption tomake. The wattless energydoes were no brushes g, the voltage across the primaries of transformers F would necessarily rise when this displacing occurs because these transformers-are series transformers and must develop in their secondaries a current proportionate to that in their primaries and for the same reason, the rectifier G must give out to the circuit E? a current proportionate to that which it receives.

The displacing of the brushes 9, however, causes a sub-' stantial difference of potential to be developed between them and so causes a current to be by-passed into the local circuit G By proper adjustment of the circuit the voltage across the primaries or transformers F may be kept at all times proportional to the current therein,

whereby changes of power factor reducing the voltage across brushes 9 will also reduce the current in the regulating coil E By my invention, therefore, I am enabled to produce a current in E that varies in accordance with changes of current of transformers F only when there is nodhange of power factor. If, however, there is a coincident change of current and change of power factor, the voltage in the coil E will be a resultant of these changes, an increase of current in the alternating current circuit tending to increase the current in the coil E while .a decrease of power factor tends to decrease it. In this way the regulation is not affected by the wattless current component of the apparent energy.

It is obvious that the principle of my invention as herein described may be applied" to many different specific systems either where voltage or where current regulation is the dominating regulation. In the present case the current regulation is the dominating regulation. Strictly speaking the regulation illustrated and described is not a load regulation because it is a regulation that is independent of voltage changes. It is, however, a regulation that, broadly speaking, isa load regulation in the same sense that a regulation by current changes of a direct current circuit is frequently denominated a load regulation. it should also be noted that the specific apparatus employed to by-pass some of the regulating current in accordance with changes of power factor is applicable to a mimbor of purposes. In- -deed, the circuit G might be used without the regulating circuit connected to the brushes 1/ as a means of indication or regulation. v

Having thus des ribed my invention, what I claim as new and desire to protect by Letters Patent. is:

1. The combination of an alternating current generator, 0 regulating buttery therefor, regulating apparatus for lvarying the battery action and means for controlling the nation of said apparatus in accordance with the resultant of the values of the current of the alternating current'circ.1it and the power factor. thereof.

L. The combination of an alternating current generator, :1 regulating buttery therefor regulating apparatus for varying the battery action, means for supplying a regulating current to said apparatus, and means for changing the ratio between themcgulating current and -that of the altcrnuting current generator in accordance with changes of power factor of thc ulteruuting current circuit.

3. The combination of an alternating current generator,

a regulating battery therefor, regulating apparatus for varying the battery action, means for regulating said appurat'us responsively to variations of one of the components of the alternating current energy. and means for oppositely regulating said apparatus in accordance with the wattless current of the alternating current circuit.-

4. The combination of an alte'rnating current generator, :1 regulating battery therefor, regulating apparatus for varying the battery action, means for supplying a regulating current to said apparatus, and means for by-passing current from saidregulating apparatus in accordance with changes of power factor of the alternating current circuit.

5. The combination with an alternating current circuit,'.

a-reguiating apparatus, a regulating circuit therefor, and means for bypassing current from said circuit in accordance with changes of power factor of the alternating current circuit' 6. The combination with'an alternating current circuit of a compensatory storage apparatus in operative relation therewith, regulating apparatus for said storage apparatus connected to-the alternating current-circuit, and means for affecting the action of said regulating apparatus by power factor changes of the alternating current circuit. v

7. The combination of an alternating currentrgenerator, compensatory storage apparatus in operative relation thereto, and means for afiecting the action of the storage apparatus resporisively to power factor changes of the system. I 7

8. An alternating current generator, a compensatory storage battery, regulating devicestherefor, apparatus connected to the circuit of the alternating current generator for determining the current for controlling the regulating devices, and means for causing out-of-phase relations of the electro-motive-force and current of the alternating current circuit to act upon said apparatus to modify said current.

0. The combination of an alternating current generator,- its load and a regulating batery therefor, regulating apparatus for varying the battery action and means for controlling the action of said regulating apparatus, one it the factors of said control being the power factor of the alternating current circuit.

10. A rectifying device of the induction'type having a pair of brushes engaging commutator segments haviffg practically zero difference of potential and a circult con necting said brushes.

11. A rectifying device of the induction type, having two sets of brushes engaging commutator segments dlsplaried substantially ninety electrical degrees.

12. A rectifying device of the induction type having a pair of brushes adjusted to engage commutator segments having practically zero potential when the power factor is unity.

13. A rectifying device of the induction type having two sets of brushes adjusted to engage the commutator at points corresponding respectively to maximum and zero difierences of potential when the power factor is unity.

14. A rectifying device of the induction type, a regulating circuit in connection with the usual commutator brushes thereof, a set of commutator brushes electrically displaced with relation to the usual brushes, and a circuit connected to said displaced brushes.

15. A rectifying device of the induction type, a regulating circuit in connection with the usual commutator brushes thereof, a set of commutator brushes displaced ihstantlally ninety electrical degrees with relation to the usual brushes, and a circuit connected to said displaced brushes.

16. A rectifying device having induction hut devoid of motor action, having in adition to the usual commutator brushes, 9. set of brushes engaging the commutator to-receive substantially zero potential when the power factor is unity.

17. A rectifying device having induction but devoid of motor action, a direct current regulating circuit fed from brushes bearing on the commutator thereof, a second clr cult, 'and an additional pair of commutator brushes feeding the same 1B. A rectlfyihg device having induction but devoid of motor action, a direct curent regulating circuit fed from .brushea bearing on the commutator thereof, a set of comsecond circuit connected thereto;

mutator brushes displaced suhstantiailyninety electrical degrees relatively to theusual:commutatorbrushes, anda:

' '15). A rectifying'device' having induction devoid of motor action, a direct current regulating circuit fed from brushes hearing'on'the' commut'atorthereof, a setof comthere is a departure from a predetermined power fsctor.

22. The combination" of aregulating circuit, a rectifier .ofthe inductiontype supplying the current thereto, a local circuit,- and means for supplying. current thereto in accordauc' .tvithmhanges of power factor.

I 23. The combination of aregulating circhit, a rectifier of the induction type-supplying the 'curreht'th'etetma local circuit, means for supplying current thereto inaccordance witlr'c hanges of power factor, and means forv adjusting the resistance of the'lo'cal circuit.

24. The combination of an alternating current circuit, seriestransformers'therein, a rectifying device of the induction type supplied "from said series transformers, adire'ct currentregulating circuit suppliedfro'm the rectifying devices; and means .for' diverting current from said rectifying device w'henthe power factordeparts from a predetermined value.

I l I 25. The'combination of an"alternating'current circuit,

.series transformers therein, a rectifying devicel of the induction type supplied from the'series"transformers, two

sets of electrically displaced commutator brushes for said' rectifier, a regulating circuit connected to one set'of brushes, and a second circuit connected to the other brushes.

- 26. The combination of an alternating current circuit, series transformers therein, arectifying-device of the induction .type supplied from-the'series transformers, two

sets of electrically displaced commutator brushes for said rectifier, a regulating circuit connected to one set of brushes, a second circuit connected to theother brushes and means for adjusting the resistance of said second circuit. a

27. The combination of an alternating current circuit, series transformers therein, a rectifying 'devlceof the induction l'ypc supplied from said seriestransformers, a direct current regulating circuit supplied from the rectifying device, and means for modifying the relation between the transformer current and that of the regulating circuit as thcpower factor changes.

28. The combination of an alternating current circuit, series transformers therein, a rectifying device of the induction type supplied from said series transformers,

, brushes engaging the rectifier commutator at points of normal maximumdifferencc of potential, a regulating circuit connected to said brushes, brushes engaging said commutator at points of normal minimum difference of potential, and a circuit connected to the latter, brushes.

29. The combination of an alternating current circuit, series transformers therein. a rectifying device of the induction type supplied from said series transformers. brushes engaging the rectifier commutator at points of normal maximum dilference of-pgteutial, a regulating circuit connected to said brushes, brushes engaging said commutator at points of normal minimum difference of potential. and u-circuit connected tothelatter brushes.

30. The combination of an alternating current circuit, a rectifying device supplied therefrom, a dynamo, a corn trolling coil therefor fed from said rectifying device, and" means for varying the current supplied to said 'coil ac- ;cording to power factor changes in the alternating current circuit.

'trolllng coil therefor fed from said rectifying device, and

' means "an! diverting current from the rectifier according to '32..'1 he combination of an alternating currentcircuit, a rectifying device of the'in'duction type supplied therefrom, a dynamo, a controlling coll therpfor fed from brushes bearing on the rectifier commutator, a second set coil therefor fed from brushes hearing on the rectifier com-.

mutator. a second set of commutator brushes; electrically displaced withjrelatlon to the usual brushes, and a local circuit-connected to said second set of brushes.

1 '34. The combination of an alternatingcurrent circuit, series-transformers 'therein, a rectifying device supplied therefrom'ya dynamo, a controlling coiltherefor fcd from' brushesfbearing' on the rectifier-commutator, and means for varying the ratio between the current ofthe series .tran'sformers and that of the controlling coil'according to chnngesof power factor of the alternating current circuit.

' 35.".lhe combinatignof an alternating current generator, a rectifying device connected thereto, a storage battery also connected thereto, regulating apparatus for varying.

the battery act ion,,a controlling coil therefor/a rectifying devlcesupp'lying current to said controlling .coil and connected. to the alternating current generator,- and means for varying the-current in said coil accordingto changes of power factor in the alternating; current circuitfl.

3G. The combination of an alternating current generator, a rectifying device connected thereto, a storage'battry also connected thereto, regulating apparatus for varying the battery action, a controlling coil therefor,.transf0r'in- .ers inseries with the alternating current generator, a rec-- tifying device connected thereto, connections from the'rectifying device to said-controlling coil, and means for vary ing' the ratio between the said transformer current and that in the controlling coil according to changes of power factor of the alternating current circuit. I

Il'L The combination of an alternating current generator, a rectifying device connected thereto, a storage battery also connected thereto, regulating apparatus for varying the battery action, a controlling coil therefor, transformers in series with the alternating current generator, :1 rectifying deviceconnected thereto, connections from the rectifying device to" said 1 controlling coil, and means for diverting current'from saidrectifying device as the power factorof the alternating current circuit changes.

, 38. The, combination of an alternating current generator, a rectifying device co'nnected thereto, a storage battery also connected thereto, regulating apparatus for varying the battery action, a controlling coil therefrom, a rectifier of the induction type connected to the alternating current generator, :1 local circuit, two sets of brushes bearing on the rectifier commutator, one set electrically displaced with reference to the other, and connections from one set' '39. The combination of an alternating current generator, a rectifying device connected thereto, a storage battery also connected thereto, regulating apparatus for varying the battery action, a controlling coil therefor. a rectifier of the induction type connected to the alternating current generator. a local circuit, two sets of brushes bearing on the rectifier commutatorfone set electrically displaced with reference to the'other, connections from one set of brushes to the controlling coil and from the other-set to a local circuit, and means foradjusting the resistance of said local circuit.

40. The combination of an alternating current generator, a rectifying device connected thereto, a storage battery also connected thereto, regulating apparatus for varying the battery aciion,-a controlling coil therefor, i1 rectifier of the induction type'connected to the alternating current vgenerator, a set of brushes bearing on the rectifier commututor and connected to'sald controlling coll, a local circuit, and a set or brushes c'onucctgd to said locsl circuit changes of power factor of the alternating current circuit.

transformers, a set of brushes bearing on the, rectifier com-I mntntor and connected to said controliingcoll, a local 'clrcult, and a set of brushes connected -thereto and engagingthe commutator at points of substantially zero difference t of potential when the power factor otthe alternating current circuit is unity.

42. The combination of an alternating current generator. a rectifying device connected thereto, a storage battery also connected thereto. regulating apparatus for varying the battery action. a controlling coil therefor, series trans-- formers therein, a rectifying device connected to said transformers. a set of brushes bearing on the rectifier commutator and connected to said controlling coil,'a local circuit. a set of brushes connected thereto and engaging the commutator at points of substantially zero difference of potential when the power factor of the alternating current set.

Correction in Letters Patent No. 869,244.

circuit is unity. and means for adjusting the resistance of the local circuit. V

43. A rectifying device of the induction type and means for driving it in synchronism with one of the factors of an alternating load, a commutator and collector rings for the rectifier, means to electrically connect the collector rings and the alternating circuit, means for interllnking the fields due to the alternating and direct currents, and two setsof brushes for the commutator, one set displaced practically ninety electrical degrees relatively to the other 44. A rectifying device of the induction type and means for-driving it in synchronlsm with one of the factors of an alternating load, a commutator and collector rings for the rectifier, means to electrically connect the collector rings and the alternating circuit, means for interlinking the fields due to the alternating and direct currents, and two sets of brushes for the commutator, one set electrically displaced relatively to the other set and means for utilizing the current from one set of brushes.

45. A rectifying device of the induction type and means [satin] for driving it in synchronism with one of the factors of an'alternating load, a commutator and collector rings for the rectifier, means to electrically connect the collector ringsand, the alternating circuit, means for interlinking the fieldsdu e to the alternating and direct currents, and

two sets of brushes forfth commutator, one set electrically displaced relatively to the other set, the current from one [set being utilized, the other set by-passing current from the first set whenthe driving power is out of phase with the alternating current to be rectified.

' 46. A rectifying device of the induction type and means for driving it in synchronism with one of thefactors of an alternating load, a commutatorand collector rings for.

the rectifier, means to electrically connect the collector ringsfand the alternating circuit, means forinterlinking the fields due to the alternating and direct currents and two sets of brushes for the commutator, one set electrically displaced relatively to the other set and means for obtaining an alternating current. to .be rectified, varying as the factor to be measured.

47. A device for producing a current power factor changes comprising a' rectifying device having two sets of commutator brushes, the current dividing between the two sets according tothe power factor.

48. A rectifying device of the induction type fol-poly phase currents and means for driving-it in synchronism with one of the factors of an alternating load, a com- .mutator and collector rings for the rectifier, means to electrically connect the collector rings to the ditferent phases of the alternating circuit, means for interlinking the fields due to the alternating and direct currents, and

corresponding to two sets of brushes for the commutator, one set -electrically displaced relatively to the other set.

49. An alternating current circuit, 'a regulating storage battery, a controlling apparatus'for the'battery, and'means for acting upon said controlling apparatus in accordance with variations in the apparent load of the alternating current circult as modified by the power factor changes therein.

In testimony whereof, I have signed my'jnametothis specification, in the presence of two subscribing witnesses.

ALBERT. SQ HUBBARD. Witnesses:

Enwnv Sauna, Alvin DALI.

It is hereby certified that in Letters Patent No. 869,244, granted October 29, 1901, upon the application of Albert SrHubbard, of Bellevilio, New Jersey, for an 'improve-; ment in Alternating-Current Apparatus, an errorappears in the printed-specification requiring correction, as follows: In line 43, page 1, the word f'factiond should read factor and that the said Letters Patent should be read with this correction therein that the same may conform to the record of, the case inthe Patent Oifico.

Signed and sealed this 17th day of December, A. D,., 1907.

o. o. BILLINGS,

Acting of 

